DESCRIPTION (Adapted from the application): With the dramatic expansion and increased methodologic sophistication in Alzheimer's disease (AD) research, demands on the clinical core for clearly defined samples of persons with AD and age-matched controls have become more complex. A sample of subjects appropriate for one type of investigation (such as a clinical treatment outcome trial) is often not appropriate for other types of studies (for example, a case-control epidemiologic study or genetic linkage analysis). Still, other types of samples are needed for training clinicians to manage the multiple clinical problems expressed during the course of AD. To meet these multiple demands, the clinical core has developed and will continue to provide multiple samples of AD patients and normal healthy control subjects suitable for supporting the subject recruitment needs of a broad range of research and clinical training in AD. The clinical core will continue to include probable AD and nondemented older controls selected for maximum appropriateness for participation in clinical studies. In addition, subjects with non-AD neurodegenerative demanding disorders and mild cognitive impairment will be recruited and followed in the clinical core. The genetics sample includes patients with familial AD and related familial dementias who are followed for participation in linkage analysis and other genetic studies. Clinical core personnel support and interact with population-based cohorts of AD and normal control subjects appropriate for epidemiologic studies and which provide additional sources for accession of postmortem brain tissue. Through all these subject populations, subjects are provided to meet the research needs of ADRC investigators, other appropriate investigators in the broader University of Washington research community, and investigators at other institutions.